R, G, B = map(int, input().split())

def solve(r, g, b):
    rgb = [r, g, b]
    rgb.sort()
    r, g, b = rgb
    s = r
    g -= r
    b -= r
    if b >= g * 3:
        s += g
        b -= g * 3
        s += b // 5
        return s
    r2 = (b - g) // 2
    s += r2
    g -= r2
    b -= r2 * 3
    if g == b:
        n = g//4
        s += n*2
        g -= n*4
        if g == 3:
            s += 1
        return s
    if g + 1 == b:
        n = g//4
        s += n*2
        g -= n*4
        b -= n*4
        if g == 2 or g == 3:
            s += 1
        return s
        
 
print(solve(R, G, B))